The inventions described herein may be manufactured, used and licensed by or for the U.S. Government for U.S. Government purposes.
1. Field of the Invention
The present invention relates to control devices for rounds shot by artillery and, more particularly, to a control device for automatically and sequentially making safe and then arming a fired round.
2. The Related Art
A need exists for safety controls during the firing of artillery submunitions which ensure that the detonator device (fuze) is safe during the initial firing stage but which also ensures that the fuze is armed at the proper time. To the extent that the problem has been previously addressed, current proposals suffer shortcomings and are less than fully satisfactory. One application of such a control device is for SADARM submunitions developed by the U.S. Army but such a device could be applied to other artillery submunitions as well.
According to the invention, there is provided a safing and arming device for artillery submunitions which meets stringent safety and arming requirements. The device is compact and rugged as well as highly reliable and effective.
In accordance with a preferred embodiment of the invention, there is provided a safing and arming device for a warhead or round which is to be launched by a rifled gun and which includes at least one submunition, the device comprising:
a housing;
a detonator and lead cup disposed in spaced, aligned relation within said housing;
a slider disposed in the housing between the detonator and lead cup and including an opening therein, the slider being movable between a first, safe position wherein a portion of the slider spaced from the opening is disposed between the detonator and lead cup so as to act as an interrupter, and a second, armed position wherein the opening is in alignment with the detonator and lead cup and the device is thus armed;
a setback sensor disposed in the housing for initially locking the slider in the safe position and for, responsive to a setback force produced at gun launch, unlocking the slider; and
an ejection sensor disposed in the housing for initially locking said slider in the safe position and for continuing to lock the slider against movement to the armed position during a period between gun launch and exiting of the warhead from the gun, and for, responsive to the ejection force produced at the exiting of the warhead from the gun, unlocking the slider to enable movement thereof to the armed position.
Preferably, the device further comprises a slider spring for biasing said slider into said safe position. The slider spring preferably comprises a coil spring producing an axially acting force against one end of the slider.
Preferably, the setback sensor comprises a setback sensor member received in a cavity in the housing and the device further comprises a setback spring for biasing the setback sensor member towards engagement with the slider. The setback spring preferably exerts a spring force orthogonal to an axially active spring force produced by the slider spring. The slider preferably includes an abutment portion having surface engaged by the setback sensor member in the safe position of the slider. The setback spring is compressed by the setback force so as to disengage the setback sensor member from the abutment portion and the abutment portion preferably includes a further surface engaged by the setback sensor member after movement of the slider to the armed position thereof so as to provide locking of the slider in the armed position by the setback sensor member.
Preferably, the slider includes a recess therein, the device further comprises an ejector spring received in the recess, and the ejection sensor comprises an ejection sensor member received in the recess and biased by the ejection spring against a portion of the housing in a locking position of the ejection sensor member. Advantageously, the ejection spring exerts a spring force orthogonal to an axially acting spring force produced by the slider spring. Preferably, a portion of the housing includes a stop member and the ejection member engages the stop member responsive to movement of the slider caused by the setback force to thereby limit the movement of the slider. The ejection spring is compressed by the ejection force to disengage the ejection sensor member from the stop member and to unlock the slider to permit movement of the slider to the armed position. The movement of the slider to the armed position causes positioning of the ejection sensor member on the other side of the stop member and a diminishing of the ejection force enables the ejection spring to bias the ejection sensor member in a locking position thereby locking the slider in the armed position.